JP4787000B2 - Elastic mold and method for producing molded article using the same - Google Patents

Description

  The present invention relates to an elastic mold, and more particularly, an elasticity formed by molding a silicone rubber composition containing a specific raw rubber-like organopolysiloxane, a specific silica-based inorganic filler having a low silanol group activity, and a crosslinking agent. The present invention relates to a mold and a method for producing a molded product using the same.

  Conventionally, metal molds are widely used to produce various molded products, but in recent years, instead of these, molds made of elastic materials such as natural rubber, chloroprene rubber, silicone rubber, That is, a method of forming using an elastic mold is known.

  In this molding method using an elastic mold, a fluid molding material is filled into the mold from the opening of the elastic mold, and then the molding material is solidified by heating or cooling. This is a method of taking out a molded product from an elastic mold. In this molding method using an elastic mold, the elastic mold is expanded by utilizing a difference in air pressure, etc., and the molded product is removed from the mold and ejected by discharging from the expanded opening. The mold is used repeatedly expanding and contracting many times.

  In the molding method using the above-mentioned elastic mold, reverse taper and mold-release gradient for mold release are not taken into consideration, so molded products with various desired designs can be obtained. It is used for molding chocolate, cheese, jelly, kamaboko, etc., and recently it has been used for stick lipsticks, stick lip balms, powder sticks, etc. It has also been adopted for solid cosmetics containing oily components (hereinafter referred to as “oily solid cosmetics”).

  Conventionally, an elastic mold is manufactured using, for example, a ceramic or glass original mold that is designed in a desired shape and, if necessary, has a desired pattern on its surface. That is, a series of operations for immersing the original mold in an elastomer latex such as natural rubber or chloroprene rubber, pulling it up to adhere the elastomer latex to the surface of the original mold, and solidifying the adhered elastomer latex is performed on the surface of the original mold. The process is repeated until a film-thickness elastomer is formed, and then the solidified elastomer is peeled off from the original mold.

  In addition, silicone rubber is applied to the surface of ceramic or synthetic resin molds to form a film, and in that state, the silicone rubber is cured, and then the cured silicone rubber is peeled off from the mold to form a hollow elastic mold. A manufacturing method is also known (see, for example, Patent Document 1).

  However, since it is difficult to obtain a high degree of dimensional accuracy for these elastic molds manufactured by the dipping method or the coating method, a high degree of dimensional accuracy is required in terms of fitting with a container and appearance quality, such as a stick-shaped lipstick. It is not suitable for forming products. Therefore, an elastic mold that can be obtained with a cured product of addition-type liquid silicone rubber as a raw material and molded with a combination of two or more molds with high dimensional accuracy has also been proposed (for example, Patent Documents). 2).

  In addition, especially when manufacturing oily solid cosmetics such as lipsticks by continuous molding, in order to reduce the influence of swelling of the elastic mold caused by the oily components in the solid cosmetics, fluorosilicone rubber and silicone rubber are used as materials. An elastic mold produced by using fluorosilicone rubber together or an elastic mold made of a resin containing a fluorine-based elastomer having a specific fluorinated polyether skeleton has been proposed (for example, Patent Document 3, Patent Reference 4 and Patent Document 5).

  By the way, normal silicone rubbers such as addition-type liquid silicone rubbers and cured products of condensation-type liquid silicone rubbers are too soft and difficult to maintain their shape unless they contain fillers. It cannot be a mold. Therefore, if a silica-based filler conventionally used in silicone rubber is blended, the shape can be maintained without impairing elasticity, and an elastic mold can be formed.

  However, when molding is performed using the above-mentioned silicone rubber elastic mold containing this general silica-based filler, there is a drawback that the gloss of the molded product cannot be sufficiently obtained due to the influence of the filler. This defect is not a big problem when the molded product is chocolate, cheese, kamaboko, etc., but it is a fatal problem in oily solid cosmetics such as lipsticks that require high surface gloss as an important product quality. It becomes.

  On the other hand, an elastic mold using fluorosilicone as a material is excellent in durability, but depending on the type of oil component, the mold release property between the elastic mold and the molded article may be deteriorated. In some cases, the remaining surface of the molded product may be lost due to adhesion to the inner surface of the mold, or the surface gloss of the molded product may not be sufficiently obtained.

In recent years, customer needs for products have been diversified, and in order to carry out a variety of products in small quantities, it is necessary to prepare a large number of elastic molds having different shapes. Therefore, an elastic mold is required to be economical in terms of cost rather than durability, but in this respect, an elastic mold formed using an expensive material such as fluorosilicone is naturally expensive. It is not suitable for high-mix low-volume production.
JP 7-8245 A JP 2000-158451 A JP 2000-290139 A JP 2000-326337 A JP 2001-038740 A

  The present invention has been made under the present circumstances as described above, and is an inexpensive elastic mold that is excellent in releasability and can be molded into a molded article such as an oily solid cosmetic having a sufficient gloss on the surface. The issue is to provide

  As a result of earnest research on the elastic mold material that can solve the above-mentioned problems, the present inventors have found that a specific raw rubber-like organopolysiloxane, a specific silica-based inorganic filler having a low silanol group activity, and a silicone containing a crosslinking agent It has been found that the above object can be achieved by using an elastic mold produced by molding a rubber composition, and the present invention has been completed based on these findings.

That is, the present invention includes the following components (A) to (C),
(A) Organopolysiloxane having a polymerization degree of 3,000 to 8,000 represented by the following average composition formula (1)
RnSiO _{4-n / 2} (1)
Wherein R is the same or different unsubstituted monovalent hydrocarbon group, and n is 1.98 to 2.0.
It is a positive number of 2. )
(B) Filler containing at least the following component (b-1) and component (b-2) (b-1) One or more selected from the group consisting of crystalline silica powder and diatomaceous earth (b- 2) One or two or more types selected from the group consisting of wet silica powder and dry silica powder having a specific surface area (BET method) of 100 m ² / g or less (C) A silicone rubber composition containing a crosslinking agent is molded. This is an elastic mold.

  Moreover, this invention is said elastic shaping | molding die whose crosslinking agent of a component (C) is an organic peroxide.

  Furthermore, in the present invention, in addition to the components (A) to (C), the silicone rubber composition further contains a non-reactive silicone oil such as dimethylpolysiloxane having a viscosity of 0.1 to 20 mPa · s as the component (D). The above-mentioned elastic mold.

  Furthermore, the present invention is a method for producing a molded article such as a solid cosmetic containing an oily component, wherein the elastic mold is filled with a flowable molding material, solidified, and then taken out from the elastic mold.

  The elastic mold of the present invention has good releasability, and can impart sufficient gloss to the surface of a molded product such as an oily solid cosmetic molded using the mold. And since this elastic mold can be made into a free shape with appropriate flexibility, it can be used advantageously in molding oily solid cosmetics such as lipsticks and other products that require gloss on the surface as an important quality. Therefore, it is possible to mass-produce a product with a beautiful appearance having both a shape that can only be obtained by an elastic mold and a surface gloss that has never been obtained before.

  In the present specification, the “silicone rubber composition” means a curable composition before finally being cured and molded into a silicone rubber molded body. In addition, the “elastic mold” of the present invention is manufactured by molding from a silicone rubber composition. After molding, the mold becomes a mold for molding a fluid molding material into a certain shape. Is.

  The elastic mold of the present invention is produced by molding a silicone rubber composition as described above. The organopolysiloxane of component (A), which is one material of this silicone rubber composition, has the following average composition formula: It is a raw rubber-like compound represented by (1) and having a degree of polymerization of 3,000 to 8,000.

RnSiO _{4-n / 2} (1)
(In the formula, R is the same or different unsubstituted monovalent hydrocarbon group, and n is a positive number of 1.98 to 2.02.)

  Examples of R in the average composition formula (1) include alkyl groups such as methyl group, ethyl group, propyl group, and butyl group, and cycloalkyl groups such as cyclohexyl group.

  The organopolysiloxane of the component (A) represented by the above average composition formula (1) is, for example, a dimethylsiloxane unit as a main component, a methylvinylsiloxane unit, and a degree of polymerization of 3,000 containing a vinyl group derived from the dimethylvinylsiloxane unit. -8, 000 rubber-like organopolysiloxanes, for example, by cohydrolyzing and condensing one or more selected organohalogenosilanes, or cyclic polysiloxanes (siloxane trimers or Tetramer, etc.) can be obtained by ring-opening polymerization using an alkaline or acidic catalyst. This is basically a linear diorganopolysiloxane, but is partially branched. May be. Further, it may be a mixture of two or more different molecular structures.

  In this component (A), the vinyl group content is 0.001 to 20 mol%, preferably 0.025 to 10 mol%. If the vinyl group content is too small, the physical strength of the elastic mold may not be obtained, and if it is too large, it may become too hard or brittle when vulcanized.

  In addition, the filler of component (B) used as a raw material for the silicone rubber composition is an elastic molding that improves the shape retention of the silicone rubber and has shape retention that can maintain the dimensional accuracy of the molded product even during repeated molding operations. In addition to being essential for forming a mold, it is possible to impart sufficient gloss to the surface of oily solid cosmetics such as lipsticks when molded.

This component (B) has at least one selected from the group consisting of crystalline silica powder and diatomaceous earth (component (b-1)), wet silica powder and specific surface area (BET method) of 100 m ² / 1 type, or 2 or more types (component (b-2)) selected from the group consisting of g or less dry silica powder.

  In the present invention, by combining the component (b-1) and the component (b-2) as fillers, it is possible to maintain the dimensional accuracy of the molded product in a repetitive molding operation using an elastic mold and to sufficiently gloss the surface of the molded product. It was impossible to predict from the individual effects of the filler having a low silanol group activity.

  Among the components (b-1), examples of the crystalline silica powder include quartz powder and novaculite (light sandstone). The crystalline silica powder is not particularly limited, but preferably has an average particle size of about 2.5 to 5 μm. Moreover, what baked this besides normal diatomaceous earth can be used as diatomaceous earth.

Among the components (b-2), as wet silica powder, for example, commercially available products such as Nipsil VN3-LP (manufactured by Nippon Silica Kogyo Co., Ltd.), HI-SIL (manufactured by PPG) can be used. Examples of dry silica powder having a surface area of 100 m ² / g or less include Aerosil 50 (manufactured by Nippon Aerosil Co., Ltd.) (specific surface area = 50 m ² / g), Aerosil 100 (manufactured by Nippon Aerosil Co., Ltd.) (specific surface area = 100 m ² / g). Commercial products such as these can be used.

  Among the fillers of the component (B), the component (b-1) is preferably blended in an amount of 3 to 150 parts, particularly 5 to 100 parts, per 100 parts of the component (A). Moreover, it is preferable that a component (b-2) is 1-50 parts with respect to 100 parts of the said component (A), especially 3-40 parts.

  In addition to the component (b-1) and the component (b-2), the filler of the component (B) is known in a quantitative and qualitative range depending on the purpose without impairing the effects of the present invention. Other fillers can be blended.

In addition, crystalline silica powder, diatomaceous earth, wet silica powder, and dry silica powder having a specific surface area of 100 m ² / g or less mentioned as the component (b-1) or component (b-2) are all fillers having low silanol group activity. It is. In contrast, conventionally used dry silica (fumed silica) usually has a specific surface area of more than 100 m ² / g, and the powder has many silanol groups due to the size of the specific surface area. High activity. And when this dry silica with high silanol group activity is used for molding lipsticks and the like, gloss cannot be imparted to the surface of molded articles such as lipsticks, which are molded products, and surface gloss is an important quality. It cannot be used to form products.

  In addition, even when each of the above fillers having low silanol group activity is used alone, shape retainability capable of maintaining the dimensional accuracy of the molded product by repeated molding operations, and sufficient gloss on the surface of the molded product. It is difficult to achieve both.

  Furthermore, the crosslinking agent of component (C), which is a raw material of the silicone rubber composition, is not particularly limited as long as it can crosslink the component (A) organopolysiloxane. A combination of a platinum-based catalyst and an organohydrogensiloxane is preferred.

  Specific examples of the organic peroxide include p-methylbenzoyl peroxide, benzoyl peroxide, dicumyl peroxide, 2,5-dimethyl-2,5-bis (tert-butylperoxy) hexane, and the like. can do. On the other hand, among platinum catalyst and organohydrogensiloxane combinations, platinum catalysts include those in which solid platinum is supported on a carrier such as platinum black, alumina, silica, chloroplatinic acid, alcohol-modified chloroplatinic acid, chlorinated A complex of platinum acid and olefin, a complex of platinum and vinylsiloxane, and the like can be given.

  In the present invention, it is particularly preferable to use an organic peroxide as a crosslinking agent for the component (C).

  The amount of the crosslinking agent of component (C) is not particularly limited as long as it is an amount sufficient for crosslinking (effective amount). However, when an organic peroxide is used as component (C), organo (component) (A) is used. The amount is preferably 0.1 to 5 parts with respect to 100 parts by mass of polysiloxane (hereinafter abbreviated as “parts”). It is preferably 2000 ppm.

  In the production of the elastic mold of the present invention, it is preferable that a nonreactive silicone oil (component (D)) is further contained in the silicone rubber composition in addition to the above components. By including a non-reactive silicone oil in the silicone rubber composition, when the elastic mold is molded, the non-reactive silicone oil does not bleed on the surface of the elastic mold without sweating. Since it becomes easy, mold release property can be improved more.

  Examples of the non-reactive silicone oil that can be used as the component (D) include silicone oils that do not have silanol groups or alkoxy groups. Specific examples include liquid dimethylpolysiloxane, methylphenylpolysiloxane, and the like. However, in the present invention, dimethylpolysiloxane which is liquid and has a viscosity of 0.1 to 20 mPa · s is particularly preferable. As such a non-reactive silicone oil, commercially available products such as KF96 (manufactured by Shin-Etsu Chemical Co., Ltd.) can also be used.

  The compounding amount of the non-reactive silicone oil of component (C) is preferably 0.5 to 20 parts, particularly 1 to 10 parts, relative to 100 parts of the organopolysiloxane of component (A).

  In addition, in the production of the elastic mold of the present invention, a dispersant may be further contained in the silicone rubber composition in addition to the above components. By containing this dispersant in the silicone rubber composition, the efficiency of dispersing the filler as the component (B) can be increased.

  Examples of the dispersant include silanol group-containing low molecular weight (polymerization degree of 100 or less) organopolysiloxane and hexamethylsilazane.

  The elastic mold of the present invention can be produced by molding the silicone rubber composition according to a conventional method. The following method is mentioned as an example of a preferable manufacturing method. That is, first, with respect to 100 parts of the organopolysiloxane as the component (A), the component (B-1) is 3 to 150 parts, more preferably 5 to 100 parts, among the fillers of the component (B). (B-2) 1 to 50 parts, more preferably 3 to 40 parts are added and mixed, and an effective amount of the component (C) crosslinking agent is further added and mixed. At this time, the non-reactive silicone oil of component (D) or the dispersant of component (E) may be mixed.

  Next, the silicone rubber composition is injected into a mold having a desired shape, and this is polymerized and cured (hereinafter abbreviated as “curing”), whereby an elastic mold can be suitably obtained.

  As a method for curing the silicone rubber composition, a method of heating the above mixture to 150 to 200 ° C., preferably 160 to 180 ° C. can be used. In this case, a combination of 0.1 to 5 parts of an organic peroxide or 1 to 2000 ppm of a platinum-based catalyst and an organohydrogensiloxane as a crosslinking agent for the component (C) may be added to the silicone rubber composition. It is preferable because it can be efficiently cured by a heating operation.

  The elastic mold of the present invention may be transparent or opaque, and the color may be any color such as white, gray, black, ocher, brown, red, blue. Needless to say, dyes and pigments can be added as appropriate for this coloring.

  The molding method for forming the elastic mold of the present invention using the silicone rubber composition is not particularly limited to the above method, and is generally used in injection molding, pressure molding and the like. There are methods available.

  The elastic mold of the present invention thus obtained has a hardness value of 15 to 60 in a measured value (JIS-A) using a spring type hardness tester (durometer: type A) defined in JIS K6249. It is preferably within the range, and more preferably within the range of 20 to 45. If the hardness is lower than 15, the durability is inferior, and the mold may be deteriorated as it is repeatedly used several times, and the dimensional accuracy of the molded product may not be maintained. Also, when the elastic mold is expanded using the air pressure difference and the molded product is peeled off from the mold, if the hardness is higher than 60, the elastic mold is difficult to expand and difficult to take out. The surface gloss may be impaired.

  In order to produce a molded product using the mold of the present invention described above, according to a conventional method, an elastic mold is filled with a flowable molding material that is a material of the molded product, and this is cooled, solidified, and then elastic molded. Just take it out of the mold. In this case, a holding tool can be attached to the elastic mold according to the characteristics of the molded product. For example, in the case of a lipstick, if a container or a middle dish is attached to the molding material injection port side of the elastic mold, it becomes easier to remove from the elastic mold without damaging the lipstick.

  By the above method, the molding material can be cooled and solidified, and the resulting molded product can be taken out in accordance with a known method. For example, the taking out can be performed by blowing air into an elastic mold by an appropriate means and expanding it. Alternatively, a method of applying a force to the elastic mold by some means to deform it can be used.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated further in detail, this invention is not restrict | limited at all by these Examples.

Manufacturing example 1
A sheet-like elastic body was prepared as a test product by the following method.
Test product 1:
Dispersed in 100 parts of rubber-like organopolysiloxane consisting mainly of dimethylsiloxane units, consisting of methylvinylsiloxane units and vinyl content of about 0.24 mol% derived from dimethylvinylsiloxane units, and having an average degree of polymerization of about 5,000. 0.5 parts of diphenylsilanediol as the agent, 25 parts of crystalline silica as the filler [trade name: Crystallite VX-S, manufactured by Tatsumori Co., Ltd.], wet silica [trade name: Nipsil LP, manufactured by Nippon Silica Kogyo Co., Ltd.] 5 A silicone rubber composition a was prepared by heat treatment at 170 ° C. for 2 hours.

  Paste of silicone rubber composition a containing 25% by mass of 2,5-dimethyl-2,5-bis (tert-butylperoxy) hexane as a crosslinking agent (curing agent) in 100 parts of the silicone rubber composition a In other test products, the same concentration of 2,5-dimethyl-2,5-bis (tert-butylperoxy) hexane was added to the base silicone rubber composition. 2 parts were kneaded, and the resulting mixture was cured at a molding temperature of 165 ° C. for 10 minutes at a molding pressure of 8 MPa, and molded into a 150 mm square, 2 mm thick sheet-like elastic body.

Test product 2:
To 100 parts of the silicone rubber composition a, 2 parts of a cross-linking agent-containing paste and 5 parts of dimethylpolysiloxane oil having a viscosity of 10 mPa · s were added, and a sheet-like elastic body having a thickness of 2 mm was molded in the same manner as in the test product 1 below.

Test product 3:
To 100 parts of the silicone rubber composition a, 2 parts of a cross-linking agent-containing paste and 10 parts of dimethylpolysiloxane oil having a viscosity of 10 mPa · s were added. Thereafter, a sheet-like elastic body having a thickness of 2 mm was formed in the same manner as in the test product 1.

Test product 4:
Dispersed in 100 parts of a rubber-like organopolysiloxane consisting mainly of dimethylsiloxane units, consisting of methylvinylsiloxane units and a vinyl content derived from dimethylvinylsiloxane units of about 3.0 mol% and an average degree of polymerization of about 5,000. 0.5 parts of diphenylsilanediol as an agent, 25 parts of diatomaceous earth [trade name: Celite SF, manufactured by MANVILL Co.] as a filler, dry silica having a specific surface area (BET method) of 50 m ² / g [trade name: Aerosil 50, Nippon Aerosil Co., Ltd.] 10 parts was added and heat treated at 170 ° C. for 2 hours to prepare a raw rubber-like silicone rubber composition b. To this silicone rubber composition b, 2 parts of a cross-linking agent-containing paste was added and treated in the same manner as in the test product 1 to form a sheet-like elastic body having a thickness of 2 mm.

Test product 5:
2 parts of a cross-linking agent-containing paste and 5 parts of dimethylpolysiloxane oil having a viscosity of 10 mPa · s were added to 100 parts of the silicone rubber composition b, and a sheet-like elastic body having a thickness of 2 mm was formed in the same manner as in the product 1 of the present invention. .

Comparative test product 1:
100 parts of a rubbery organopolysiloxane composed mainly of methyltrifluoropropylsiloxane units, consisting of a methylvinylsiloxane unit and a vinyl content of about 0.15 mol% derived from the dimethylvinylsiloxane unit and having an average degree of polymerization of about 5,000. In addition, 0.5 parts of diphenylsilane diol as a dispersant, 25 parts of crystalline silica [trade name: Crystallite VX-S, manufactured by Tatsumori Co., Ltd.] as a filler, wet silica [trade name: Nipsil LP, Nippon Silica Kogyo Co., Ltd. [Product]] 5 parts was added and heat-treated at 170 ° C. for 2 hours to prepare a composition c. 2 parts of a cross-linking agent-containing paste was added to the composition c, and the same treatment as in the test product 1 was performed to form a sheet-like elastic body having a thickness of 2 mm.

Comparative test product 2:
2 parts of a crosslinking agent-containing paste and 5 parts of methyltrifluoropropylsiloxane oil having a viscosity of 10 mPa · s were added to 100 parts of the composition c, and a sheet-like elastic body having a thickness of 2 mm was formed in the same manner as in the test product 1.

Comparative test product 3:
Dispersed in 100 parts of rubber-like organopolysiloxane consisting mainly of dimethylsiloxane units, consisting of methylvinylsiloxane units and vinyl content of about 0.24 mol% derived from dimethylvinylsiloxane units, and having an average degree of polymerization of about 5,000. 0.5 parts of diphenylsilanediol as an agent and 40 parts of crystalline silica [trade name: Crystallite VX-S, manufactured by Tatsumori Co., Ltd.] as a filler are added and heat-treated at 170 ° C. for 2 hours to obtain a composition d. Prepared. 2 parts of a cross-linking agent-containing paste was added to the composition d and treated in the same manner as the test product 1 to form a sheet-like elastic body having a thickness of 2 mm.

Comparative test product 4:
2 parts of a crosslinking agent-containing paste and 5 parts of dimethylpolysiloxane oil having a viscosity of 10 mPa · s were added to 100 parts of the composition d, and a sheet-like elastic body having a thickness of 2 mm was formed in the same manner as in the test product 1.

Comparative test product 5:
Dispersed in 100 parts of rubber-like organopolysiloxane consisting mainly of dimethylsiloxane units, consisting of methylvinylsiloxane units and vinyl content of about 0.24 mol% derived from dimethylvinylsiloxane units, and having an average degree of polymerization of about 5,000. 2 parts of diphenylsilanediol as an agent and 40 parts of wet silica [trade name: Nipsil LP, manufactured by Nippon Silica Kogyo Co., Ltd.] as a filler were added and heat-treated at 170 ° C. for 2 hours to prepare a composition e. 2 parts of a cross-linking agent-containing paste was added to the composition e and treated in the same manner as the test product 1 to form a sheet-like elastic body having a thickness of 2 mm.

Comparative test product 6:
To 100 parts of the composition e, 2 parts of a cross-linking agent-containing paste and 5 parts of dimethylpolysiloxane oil having a viscosity of 10 mPa · s were added to form a sheet-like elastic body having a thickness of 2 mm in the same manner as in the test product 1.

Comparative test product 7:
Dispersed in 100 parts of rubber-like organopolysiloxane consisting mainly of dimethylsiloxane units, consisting of methylvinylsiloxane units and vinyl content of about 0.24 mol% derived from dimethylvinylsiloxane units, and having an average degree of polymerization of about 5,000. 0.5 parts of diphenylsilanediol as an agent, 25 parts of crystalline silica [trade name: Crystallite VX-S, manufactured by Tatsumori Co., Ltd.] as a filler, and dry silica having a specific surface area (BET method) of 200 m ² / g [ [Product name: Aerosil 200, manufactured by Nippon Aerosil Co., Ltd.] 10 parts was added and heat-treated at 170 ° C. for 2 hours to prepare Composition f. 2 parts of a cross-linking agent-containing paste was added to the composition f and treated in the same manner as the test product 1 to form a sheet-like elastic body having a thickness of 2 mm.

Comparative test product 8:
2 parts of a crosslinking agent-containing paste and 5 parts of dimethylpolysiloxane oil having a viscosity of 10 mPa · s were added to 100 parts of the composition f, and a sheet-like elastic body having a thickness of 2 mm was formed in the same manner as in the test product 1.

Example 1
Physical property test of test product:
The hardness of each sheet-like sample obtained as described above was measured with a spring type hardness tester (durometer: type A) defined in JIS K6249. Thereafter, for each of these samples, lipstick bulk 1 with low lipstick hardness after stick molding, lipstick bulk 3 with high lipstick hardness after molding, and lipstick hardness after molding between bulk 1 and bulk 3 A simple releasability test was performed using the positioned lipstick bulk 2 to evaluate the releasability of each sample with respect to the lipstick and the gloss of the lipstick surface. Tables 1 and 2 show the composition and hardness of the sheet (each test product) prepared using each silicone rubber composition and the results of the simple releasability test performed by the following method.

(Blip composition for lipstick)
Lipstick bulk 1
(Component) (mass%)
1. Hydrocarbon wax 13
2. Candelilla wax 4
3. Lanolin fatty acid ester 15
4). Liquid paraffin 5
5. Diglyceryl triisostearate 4
6). Pentaerythrityl tetraoctanoate 25
7). Cetyl octoate 20
8). Sucrose fatty acid ester 1
9. Extender pigment 6
10. Coloring pigment 6.9
11. Fragrance 0.1

  The above lipstick bulk 1 was formed into a stick-shaped lipstick and allowed to stand in a thermostatic bath at 30 ° C. for 1 hour. When the bending load value of the stick was measured under the condition of 1 minute, the average value of 10 pieces was 210 g.

Lipstick bulk 2
(Component) (mass%)
1. Hydrocarbon wax 8
2. Candelilla wax 3
3. Hexa (hydroxystearic acid /
Stearic acid / rosinic acid) dipenta 5
Erythrityl 4. Lanolin fatty acid ester 10
5. Liquid paraffin 7
6). Diglyceryl triisostearate 23
7). Glyceryl trioctanoate 30
8). Propylene glycol dicaprate 5
9. Extender pigment 1
10. Pearl pigment 5
11. Coloring pigment 2.9
12 Fragrance 0.1

  The bulk 2 for lipstick was formed into a stick-shaped lipstick, and the bending load value of the stick was measured in the same manner as in the case of bulk 1 for lipstick. As a result, the average value of 10 pieces was 270 g.

Lipstick bulk 3
(Component) (mass%)
1. Hydrocarbon wax 10
2. Candelilla wax 5
3. Diisostearyl malate 20
4). Diglyceryl triisostearate 8
5. Pentaerythrityl tetraoctanoate 20
6). Isotridecyl isononanoate 20
7). Dimethylpolysiloxane 6
8). Extender pigment 5
9. Pearl pigment 5
10. Color pigment 0.9
11. Fragrance 0.1

  When the above lipstick bulk 3 was formed into a stick-shaped lipstick and the fold load value of the stick was measured in the same manner as in the case of lipstick bulk 1, the average value of 10 pieces was 339 g.

(Simple releasability test)
The lipstick bulk is melted by heating to 90 ° C. After pouring the bulk melt into aluminum pipes that are set up in advance on each sample sheet, they are cooled at room temperature, and the aluminum pipes are removed from the sheet. It was. This operation was repeated twice for each sample, and the degree of dirt on the sheet and the surface gloss of the portion in contact with the lipstick bulk sheet solidified in the aluminum pipe were observed.

  The observation results were evaluated using the following evaluation criteria (a) and (b). And the sum of each score in the evaluation criteria (a) and (b) of each sample was judged using the following judgment criteria (c). In the following evaluation criteria (A), peeling refers to a phenomenon in which a part of the surface of the lipstick bulk remains attached to the sheet, and the surface of the lipstick bulk is attached or a part of the surface is missing.

(Evaluation criteria, etc.)
・ Evaluation criteria (A)
Rating: Content 3: No peeling is observed twice, and the releasability is good.
2: A small amount of peeling is observed once in two times.
1: A clear peeling is observed once in two times.
0: The releasability is poor and clear peeling is observed both times.

・ Evaluation criteria (I)
Score: Contents 3: Very glossy.
2: There is gloss.
1: There is not much gloss.
0: Almost no gloss-no gloss at all.

・ Criteria (c)
Judgment: Contents ◎: Sum of grades is 6
○: Score sum is 4-5
Δ: The sum of the scores is 3
×: The sum of the scores is 0 to 2

(Result)

From the results of Tables 1 and 2, organopolysiloxane as component (A), crystalline silica powder or diatomaceous earth as component (b-1) as filler, wet silica powder or specific surface area as component (b-2) ( BET method) is used in combination with a dry silica powder with 100 m ² / g or less, and the molded test products 1 to 5 have good releasability with respect to lipstick, and further improve the surface gloss of lipstick. confirmed. In particular, it was confirmed that the effect was remarkable when the non-reactive and low-viscosity dimethylpolysiloxane oil was added.

On the other hand, either the comparative test product 1 or 2 using a fluorine-containing group-substituted organopolysiloxane instead of the organopolysiloxane as the component (A), and either the component (b-1) or the component (b-2) as the filler Comparative test products 3 to 6 using only one of them, and Comparative test product 7 using dry silica powder having a specific surface area (BET method) exceeding 100 m ² / g instead of component (b-2) in the filler, As for No. 8, it was not possible to obtain a good release property and surface gloss of lipstick.

Example 2
An elastic mold was produced by the following method.
Invention product 1:
A concave metal mold and a convex metal mold were prepared in which the gap when combined was the same shape as the elastic mold. On the other hand, 100 parts of the silicone rubber composition a of Example 1 was added to 5 parts of dimethylpolysiloxane oil having a viscosity of 10 mPa · s and 2,5-dimethyl-2,5-bis (tert-butylperoxy) hexane 25 as a crosslinking agent. 2 parts of a silicone rubber composition a paste containing% by mass was kneaded, and the resulting mixture was poured into the concave mold of the mold, and then the convex mold was pressed and pressed from above. Then, it was cured by heating to 200 ° C., and after 20 minutes, the convex mold was removed and the molded product was taken out from the concave mold to obtain an elastic mold of the present product 1.

Invention product 2:
The same concave and convex molds used for the production of the product 1 of the present invention were used. In the concave mold, 100 parts of the silicone rubber composition b of Example 1, 5 parts of dimethylpolysiloxane oil having a viscosity of 10 mPa · s and a cross-linking were used. A mixture obtained by kneading 2 parts of a silicone rubber composition b paste containing 25% by mass of 2,5-dimethyl-2,5-bis (tert-butylperoxy) hexane as an agent was poured. Next, the convex mold was pressed and pushed in from above. Then, it hardened on the same conditions as the said invention product 1, and the elastic mold of this invention product 2 was obtained.

Comparative product 1:
The same concave and convex molds used in the production of the product 1 of the present invention were used. In the concave mold, 100 parts of the silicone rubber composition c of Example 1 and 5 parts of methyltrifluoropropylsiloxane oil having a viscosity of 10 mPa · s were used. And a mixture obtained by kneading 2 parts of a silicone rubber composition c paste containing 25% by mass of 2,5-dimethyl-2,5-bis (tert-butylperoxy) hexane as a crosslinking agent was poured. Next, the convex mold was pressed and pushed in from above. Then, it hardened on the same conditions as the said invention product 1, and the elastic molding die of the comparative product 1 was obtained.

Comparative product 2:
The same concave and convex molds used for the production of the product 1 of the present invention were used. In the concave mold, 100 parts of the silicone rubber composition d of Example 1, 5 parts of dimethylpolysiloxane oil having a viscosity of 10 mPa · s and crosslinking were used. A mixture obtained by kneading 2 parts of a silicone rubber composition d paste containing 25% by mass of 2,5-dimethyl-2,5-bis (tert-butylperoxy) hexane as an agent was poured. Next, the convex mold was pressed and pushed in from above. Then, it hardened on the same conditions as the said invention product 1, and the elastic molding die of the comparative product 2 was obtained.

Comparative product 3:
The same concave and convex molds used for the production of the product 1 of the present invention were used. In the concave mold, 100 parts of the silicone rubber composition e of Example 1, 5 parts of dimethylpolysiloxane oil having a viscosity of 10 mPa · s and crosslinking were used. A mixture obtained by kneading 2 parts of a silicone rubber composition e paste containing 25% by mass of 2,5-dimethyl-2,5-bis (tert-butylperoxy) hexane as an agent was poured. Next, the convex mold was pressed and pushed in from above. Then, it hardened on the same conditions as the said invention product 1, and the comparative product 3 elastic mold was obtained.

Comparative product 4:
The same concave and convex molds used for the production of the product 1 of the present invention were used, and in the concave mold, the silicone rubber composition f100 parts of Example 1, 5 parts of dimethylpolysiloxane oil having a viscosity of 10 mPa · s and crosslinking were used. After pouring a mixture obtained by kneading 2 parts of a silicone rubber composition f paste containing 25% by mass of 2,5-dimethyl-2,5-bis (tert-butylperoxy) hexane as an agent, from above, The convex mold was pressed and pushed. Then, it hardened on the same conditions as the said invention product 1, and the elastic molding die of the comparative product 4 was obtained.

Example 3
Lipstick molding test:
A lipstick moldability test was performed using the elastic molds of the present invention products 1-2 and comparative products 1-4 obtained in Example 2. That is, each elastic mold was filled with a lipstick bulk dissolved by heating at 90 ° C. and cooled to form a stick-shaped lipstick. The bulk of the lipstick used was the same as that of the lipstick bulk 3 used in Example 1.

  When the molded stick-shaped lipstick is removed, the surface of the lipstick and the inner surface of the elastic mold are visually observed, and peeling (part of the lipstick surface remains attached to the inner surface of the elastic mold, leaving an adhesion mark on the lipstick surface. The releasability was evaluated using the following evaluation criteria (f) based on the presence or absence of a phenomenon in which a part of the surface of the lipstick was attached to the surface. The lipstick surface gloss was evaluated using the following evaluation criteria (ki). Then, the sum of the scores of the evaluation criteria (f) and (g) for each elastic mold was judged using the following judgment criteria (ku). The results are shown in Table 3.

(Evaluation criteria, etc.)
・ Evaluation criteria (f)
Rating: Content 3: No peeling is observed and the releasability is good.
2: A part of the peeling is observed.
1: A clear peeling is observed.
0: The release property is poor and clear peeling is observed.

・ Evaluation criteria (ki)
Score: Contents 3: Very glossy.
2: There is gloss.
1: There is not much gloss.
0: Almost no gloss-no gloss at all.

・ Judgment criteria (ku)
Judgment: Contents ◎: Sum of grades is 6
○: Score sum is 4-5
Δ: The sum of the scores is 3
×: The sum of the scores is 0 to 2

(Result)

From the results in Table 3, the component (A) organopolysiloxane is filled with crystalline silica powder or diatomaceous earth as component (b-1) and wet silica powder or specific surface area as component (b-2) (BET method). ) Is used in combination with dry silica powder having a viscosity of 100 m ² / g or less, and the non-reactive and low-viscosity dimethylpolysiloxane oil is added to form the elastic molds 1 and 2 of the present invention against lipstick. It was confirmed that the releasability was good and the surface gloss of the lipstick was good.

On the other hand, instead of the organopolysiloxane of the component (A), the comparative product 1 using a fluorine-containing group-substituted organopolysiloxane or only the component (b-1) or the component (b-2) as a filler Comparative product 2 to 3 not used, and Comparative product 4 using dry silica powder with a specific surface area (BET method) exceeding 100 m ² / g instead of component (b-2) in the filler are all good. Release properties and surface gloss of lipstick could not be obtained.

  The elastic mold of the present invention thus obtained can impart sufficient gloss to the surface of the molded product, and can maintain the dimensional accuracy of the molded product even in repeated molding operations, has good releasability and is moderate. It can be made into a free shape due to its flexibility and is also economical.

Therefore, the elastic mold according to the present invention is suitable for molding oil-based solid cosmetics such as lipsticks having a fine uneven pattern, stick-shaped oily solid powder cosmetics, etc., and these are required to have a glossy surface as an important quality. In the molding of products, it can be used to mass-produce products with a beautiful appearance having both a shape that can only be obtained by an elastic mold and a surface gloss that has never been obtained before.
more than

Claims (7)

The following components (A) to (C),
(A) Organopolysiloxane having a polymerization degree of 3,000 to 8,000 represented by the following average composition formula (1)
RnSiO _{(4-n) / 2} (1)
(Wherein R is the same or different unsubstituted monovalent hydrocarbon group, and n is 1.98 to
It is a positive number of 2.02. )
(B) Filler containing at least the following component (b-1) and component (b-2) (b-1) One or more selected from the group consisting of crystalline silica powder and diatomaceous earth (b-2) ) One or more selected from the group consisting of wet silica powder and dry silica powder having a specific surface area (BET method) of 100 m ² / g or less (C) A silicone rubber composition containing a crosslinking agent is molded. An elastic mold for molding oil-based solid cosmetics , characterized in that The elastic mold for molding an oily solid cosmetic according to claim 1, wherein the crosslinking agent of component (C) is an organic peroxide. The elastic molding die for oily solid cosmetic molding according to claim 1 or 2, wherein the silicone rubber composition further comprises a non-reactive silicone oil as component (D) in addition to components (A) to (C). The elastic mold for molding an oily solid cosmetic according to claim 3, wherein the non-reactive silicone oil (D) is dimethylpolysiloxane having a viscosity in the range of 0.1 to 20 mPa · s. The elastic molding die for molding an oily solid cosmetic according to any one of claims 1 to 4, wherein the hardness (durometer: type A) of the elastic molded body after molding is in the range of 15-60. An oily solid cosmetic material forming elastic mold according to claim 1, any one of 5, filled with a flowable molding material, after solidification this oily solid which is characterized in that taken from the elastic forming die A method for producing a molded article for cosmetic molding . The method for producing a molded article for oily solid cosmetic molding according to claim 6 , wherein the flowable molding material is a heated lipstick melt and the molded article is a lipstick.